Circumorbital cutting tool



May 7, 1940.

D. U. SHAFFER ET AL GIRCUMORBITAL CUTTING TOOL Filed May 27, 1938 Ediflamm Byaezr 4 Patented May 7, 1940 UNITED STATES PATENT OFFICE CIRCUMORBITAL CUTTING TOOL Calif.

Application May 27, 1938, Serial No. 210,446

19 Claims.

This invention is a tool for cutting pipes, stems and other bodies which may lodge in a well hole and is an improvement in tools such as shown by Luther Patent 111,221, of June 1871, in which cutters are pivoted at their upper ends to hang in slots in one member and are engaged by a relatively slidable member to be forced inwardly to cut the opposed fish body in a well hole.

' Luther shows no means for connecting the two members in a position preventing such relative movement as would swing the cutters inward, but such a provision is to be found in Anderson Patent 1,530,636, filed April 9, 1923, where the cutters l l are held as stops against member l9 which has means 2i to catch on the end of a drill pipe collar b. Thus as early as April 9, 1923, means had been provided to prevent relative movement of a member controlled by a pipe collar as to a relatively shiftable companion member as M of Anderson,

2 Without use of a conventional shear pinold at the time.

The present invention has to do with a circumorbital cutting tool involving a wholly different principle of operation than that of Luthers telescopic members and that of Anderson showing cutters used as restrainers, and. that of Kammerer Patent 1,625,414, April 19, 1927, showing a tool which depends on a constant pull of the string to force cutters l I in while the dogs 29 hold against the pipe collar, which is the mere reverse of Luthers cutting action. 1

Also the present invention is substantially different from Pickin Patent 1,772,085, August 5, 1930, showing a set of suspended cutters l5, as

in Kammerer above mentioned, but which are positively locked in outer position by a sleeve 33 which is locked by a pin 39 on the rotary, unlocking tool body I l, positioned between the cutters and the axis of the tool as set out in each of 40 his claims, and necessitating rotation of the tool body to unlock the cutters and then the lowering of the tool body as to the sleeve while this is intended to be frictionally held, by springs 31, on the pipe 47 before the cutters can be rammed 5' inward by the sliding cam IS.

The above art is cited as showing different forms in which the pioneer Luther device has been embodied with increased complexity, and an object-of the present invention is to provide a tool- 50? of this class which aims to eliminate several of the hazardous operations of the known art and to eflfect the actual cutting of the given fish body with the least possible manipulation of the tool string.

.Particularly, an object is to provide a setoi tiltable cutters bodily shiftable as a set, and to provide for normally restraining the set, and for the release of the set of cutters by a very slight upward pull of the tool string after the tool assembly has been juxtaposed to engage the fish body against end shift in either, or at least one, direction whereby to have the function of merely releasing the set of cutters, and, further, an object is to provide an automatic means to shift the set of cutters and allow the cutters to completely perform the function of cutting the fish body entirely without other motion of the tool string than merely its rotation to swing the cutters orbitally with respect'to the struck fish body, or object, if capable of being engaged in such a man- Q ner as to permit the cutting tool assembly to function.

A further object of the invention is to greatly simplify the organization, reduce the cost of construction, renewal, upkeep and operation both in 20 power and labor requirements, to enable employment of lighter parts, and increase safety of operations in a tool of the type concerned.

An additional object is to provide a fish cutting tool, which by eliminating the common step of placing the string under tension to make the cut, enables the lowering of the set of cutters to any desired point between two incidental shoulders (like collars) on the engaged string section once the cutters'have been released for cutting func- 30 tion.

Another object is to provide a cutting tool of the kind concerned, which may be operated to release its set of cutters, for shift as a unit, either by re-action of dogs against a shoulder on a fish 35 body, orby means of mechanism which may be set at any desired elevation on a string with or without shoulders.

The invention consists in certain advancements in this art as set forth in the ensuing disclosure and having, with the above, additional objects and advantages as hereinafter developed, and whose construction, combinations and details of means, and the manner of operation will be made manifest in the description of the herewith illustrative apparatus; it being understood that modifications, variations and adaptations may be resorted to within the scope, principle and spirit of the invention as it is more directly claimed hereinafter.

Figure l is a sectional, side elevation of the tool, as provided with spring dogs designed to engage, by upward pull, against a shoulder part of or on a fish body which is to be severed at a" point below the shoulder. 1 I

Figure 2 is a detail side elevation of the carrier (without the cutters) in relation to carrier releasing shears, before shear.

Figure 3 is a sectional elevation of pipe slip embracing assembly employable in the tool to effect action of the tool shears for releasing the restrained set of cutters.

An annular set of cutters 2 is shown in which the lower ends of the individually tiltable cutters are provided with pivots 3 suitably journaled in substantial cutter blocks 2 which are removably attached, in annular arrangement, about and on the upper end of a tubular carriage or herein called carrier 5. This carrier slidably fits in the foot section 6 of a tool barrel including an upper section l joining the section 6 by screw threads 8.

The barrel section ii has angularly spaced windows 9 to slidably receive the cutter blocks 3 which are readily mounted in the windows and then fastened to the carrier by respective screws ill in a simple and practical manner without having to knock down the barrel assembly, and the blocks l form splines to prevent rotation of the carrier in the barrel and they also transmit torque to the carrier when the barrel is rotated as by means of a wash-over pipe I2 screwed onto the upper end of the barrel section l; the pipe [2 being connected to a top, sub-joint l3 forming a part of a tool string by which the barrel assembly is lowered and raised and rotated as desired, in a well hole for operation on and recovery of a stuck fish, such as pipe, tubing or drillstems, in the hole; a pipe body B being here illustrated with a collar C, over-shot by the tool in Fig. 1.

The foot end of the barrel is provided with a suitable shoe M to pass over the upper end of the fish body B and means are provided above the shoe to automatically force the tiltable cutters 2 into cutting engagement with the apposite fish when the tool has been lowered into juxtaposition therewtih, and this means as here shown includes a very strong spring l5 seating at its lower end on a stationary part, as the shoe M, which here serves to compress the spring upwardly against the lower end of the slidable carrier 5 with the function of bodily shifting the set ofcutters upwardly in narrow portions 9 of the windows and in which are arranged rollers It for engaging the outer, cam faces 2 formed by the inward pitch of the upper, cutting ends of the cutters 2.

To keep the cutters 2 in upright position, as shown, until they are to be forced into fish cutting position, they are held by any suitable device, a light shear bar ll being shown spiked in the near wall of the barrel, for each cutter. A back stop key i8 is also provided to prevent outward tilt of the relative cutter in its window slot 9 Shearing load of the cutters 2 while in action on a fish is removed from the screws 10 by provision of a hook 4* on the upper end of each block 4 tointerlock with a relative keeper lug 5 on the upper end of the carrier 5.

Means are provided to prevent the spring l5 from forcing the set of cutters and their carrier upward until a predetermined time as the positioning of the set of cutters at the desired elevation as to the fish body to be cut, and means are provided to effect the release of the carrier for action of the cutters at the proper time.

As here shown, the carrier is fixed to the foot section of the barrel by a plurality of simple shear pins 241, which may be screwed into the wall of the barrel for ready renewal at will, and are transverse to vertical ways or channels 2! along the outer surface of the carrier 5 and in which ways there are slidable blades 22 whose lower ends are designed to engage the shear pins 29 when enough tension is placed on the barrel string or tool to cut through the pins 20.

The shear blades 22 are rigidly fixed to crown ring 23 which is slidably confined in the barrel section 6 for movement endwise between a shoulder 24 of the barrel and the lower end of collet 25 slidably and turnably fitting the barrel bore above the shoulder 24, and designed to move up against a stopping shoulder 26 formed by the lower end of the barrel section 1.

As indicated at X, Fig. 1, the stroke of the crown ring 23 is limited to a degree about equal to the diameter of the shear pins 29 so that that will be the total amount of pulling lift on the tool to effect the cut of the pins 29 and the full release of the carrier 5 so that this can be automatically propelled to lift the set of cutters to break their keys or bars l7 and thrust them inward against the fish body B. The collet 25 is normally held in upper position by the crown ring 23 and is provided with a set of inwardly springing arms or dogs 2'! designed to snap inwardly under collarsor shoulders C as encountered by downward movement of the tool barrel along the fish body B. I

When the tool barrel has been lowered to the lowermost possible position, or level thereabove desired, the string is. gradually elevated to bring the dogs 21 up against the next supraadjacent collar C after which enough strain will be placed on the string to cause the shear blade ends 22 to cut through the shear pins 20 as the barrel is pulled up as to the arrested dog collet 25, a distance indicated at X; which of course is arbi: trary. The dogs El are pulled up to the collar C to arrest the collet 23 only to e-fiect the. shearing of the pins 20 and not to use the collar C as a buttress for reaction of the motor spring I5. Therefore, as soon as the pins are cut the whole tool can be moved down on the pipe or fish Band the motor spring is in. full effect against the carrier '5, without any support from the pipe collar C, to forcibly tilt the cutters 2 inwardly without lean-to of the dogs 2'! on the pipe collar C since the motor spring l5 has its buttress seat on a' part of the barrel 6 of the too-l and reacts at its opposite end directly on the carrier 5.

Immediately the cutter carrier 5 is free of the.

barrel pins 26, the motor spring l5 acts to bodily push up the set of cutters 2 to break their keys I1 until the tool string is rotated, normally tothe right (looking down on the tool). It will be seen therefore, that the barrel assembly and tool string can be bodily lowered to bring the cutter ends to any desired level below the collar C at, which the cutter carrier 5 was released and above the next lower collar on the fish. At such desired;

level the tool string and its barrel assembly can now be rotated and the fish cut into by the.

orbitally driven cutters.

While the cutter carrier 5 and the shear blade;

ring 23 are co-rotatively united bythe shear blades 22 and are rotated by the spline blocks 4 in the barrel section B, the dog collet 25 is free for relative rotation of the barrel in event the dogs should bind on the engaged fish. I

3.2 slidably and turnably fitting a barrel section .33: which has one'o-r, moreclutch'nogs '34 inwardly projecting to 'hook' into abayonet slot 35 therefor" in the upper end of the coupler 32. By left-hand turn of the tool string and barrel 33 the set of slips 30 are unlocked and the barrel may be pulled up while friction spring bows 36 fixed on the coupler 32 will firmly drag on the apposed fish over which the barrel may have been lowered.

Continued lift of the barrel will move a liner 3'l-having a conical seat 38 up toengage the complementary slips 30 and these will be concurrently moved inwardly of the liner and will solidly pinch on the intruded fish body, in a manner well. known in the art of rotary well drilling tools. As soon as the slips have set onthe fish, the liner 3'! will be arrested and further-upward movement of. the barrel 33 will cause shearlblades 22 fixed to a collet 31 to out free a. relativecutter carrier.

5, as fully above described.

It is understoodethat this novel cutting mechanism isxn'ot limited to use only in the assembly here exhibited;- i

' ing a rotary barrel,.- means slidably mounted on This invention has for an object to eliminate the use of the fish. or other pipe or part as an essential means to rotate the cutters, that is tilt them, into engagement with the fish. or work part as is old in the art in Patent No. 1,625,414,

April 19, 1927, to Kammerer, and Patent No.

object being to eliminate the proposed use of a column of liquid for producing pressure for tilting the cutter blades as suggested in Fig. 7 of said Reilly et a1. patent, and an object is to eliminate the need of pulling the tool string body upward to use the fish collar as a support'to effect the actual inward tilt of the cutters after they have been released by reaction of the collar on a shearing means. These purposes are had and the disadvantages are overcome by the tool herein above disclosed. I l e What is claimed is:

l. A tool of the class described including a tubular body, a reciprocative set of inwardly tiltable cutters vin the body, a spring seated on a fixed part of the body for automatically sliding the set in one direction, means to tilt the sliding cutters, means normally restraining the sliding of the set, and means slidable in the bodyto engage and disrupt the restraining connection without action on the'spring.

2. A tool of the class described and including a rotary barrel and having a carrier splined therein, a set of inwardly tiltable cutters on the carrier, means for automatically projecting the carrier in one direction, means for normally restraining the carrier, means slidable in the barrel torelease the carrier upon a relative shift of the barrel as to the last named means and including means holdably engageable with a body to be severed and is operative on the sleeve means upon a; relative shift of the said body.

3. A tool as set forth in claim 1, and including means mounted in the barrel for individually, positively but releaseably holding the cutters in non-effective position. i

-4.' A tool as in claim 1, and including a body engaging means, independent of the cutters, controlling the release of the cutter carrier.

5. A circumorbital, body severing tool includthe barrel to holdingly set on the body against end shift, slidable and tiltable cutting meanson restraining the sliding function 'of said .cutting means, and means for releasing the restraining means for action when the holding means is effective and as the barrel is subsequently shifted on the holding means; saidautomatic means act ing independently of the body after release is ef-= fected to tilt the cutters. 6. A tool as in claim 5, and in which the cutting means is shifted to cutting position by the automatic means after the barrel has been are rested by the effective holding means; and the tool assembly being lowerable bodily aftersuch release action to effect .a cut at desired level..

'7. A circumorbital pipe, stem or other body severing tool including a rotary barrel, means movably mounted on the barrel for holding engagement with and against shift onthe body to be out, an automatic device slidably mounted on the barrel in normally restrained relation thereto and active independently of the holding-means, and .cutting means carried by said device and actual thereon and thereby 'to acutting-position on the body;.said holding meansoperative by work abutment to release the restrained device and the released device operativeat any level desired, without work abutment, to tilt the cut ters inwardly.

8. A circumorbital set of cutters, means for positioning the cutters in ineffective relation on a body to be severed and'for rotating the set when in effective position, restrained means slidably splined in the positioning means and carrying and for automatically thrusting the cutters to effective position on the body, and means engageable with the body for releasing the restrained means, the set of cutters being operative independently of support by the body, after the set is released.

.9. The combinationas in claim 8, and in which the carrying means shifts to set the cutters whilst the positioning means is held in arrest by the body or when the last named means is shifted Without such arrest.

10. A circumorbital set of cutters, a barrel for positioning the cutters in ineffective relation on work to be severed andfor rotating the set of cutters when in effective position, a cutter carrier and means for shifting it along the barrel automatically and which is in restrained position when the cutters are in ineffective relation, and means movably carried by the barrel and engageable with the work for releasing the restrained carrier whilst the barrel is arrested by such work engagement the automatic means operative, after such release, independently of work support.

11. A tool of the class described including a tool string element and a carrier slidably splined tliereon'and having a set of circumferential cutters operatively mounted thereon releasable meansv to restrain the carrier with cutters retracted, means to engage the work to effect release of the carrier, and means for automatically shifting the carrier to apply the cutter to the work free of any end thrust support or holding effect by the work so that the cut can be made a at any desired level after the carrier is released.

controlled means during a given movement of thebarrel as to the work.

13. A tool as in claim 12, and said controlled means including a connector working in the barrel adapted to holdingly interengage with the work and a spring actuated cutter to tilt thecutters without aid of the work.

14. A tool of the class described including a tool barrel, a set of tiltable cutters slidably splined in the barrel, means for automatically sliding the set in one direction in the barrel, means to tilt the sliding cutters, means normally restraining the sliding of the set, and work controlled means to disrupt the set restraining connection.

15. A tool of the class described including a rotative, string barrel tool having a slidable set of tiltable cutters, shearable means connecting the set to the barrel, work controlled means for disrupting the shearable means, and means for automatically sliding the set in the barrel to tilt the cutters to work engaging position independently of end thrust support by the work.

16. A tool string barrel having a slotted wall section, a carrier slidably fitted. in the barrel, spline blocks removably attached to the carrier and applicable thereto through the wall slots, and holding the carrier against relative rotation and work-engaging cutters pivoted on the carrier blocks, and being removable with the blocks through the slots.

17. In a tool of the class set forth, a'string barrel, a cutter carrier slidably mounted in the barrel, shearable means temporarily connecting the barrel and the carrier, a shearing device for said means slidably mounted in the barrel, and a relatively rotatable, work-controlled means for effecting operation of the said device.

18. The assembly as set out in claim 17, and in which the said device includesshear blades slid? ably splined in the carrier.

19. An assembly as in claim 17, and including means for automatically motivating the released 

